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<html lang="zh-CN">

<head>
    <meta charset="UTF-8">
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    <title>何为数据代理</title>
</head>

<body>
    <!-- 数据代理:通过一个对象代理对另一个对象中属性的操作(读/写) -->
    <script type="text/javascript">
        let obj = { x: 100 };
        let obj2 = { y: 200 }

        Object.defineProperty(obj2, 'x', {

            get() {
                return obj.x
            },

            set(value) {
                obj.x = value
            }

        })
    </script>
</body>

</html>